modules/spawn-process.js

   1 /**
   2  * (C) Copyright 2007-2008 Jeremy Maitin-Shepard
   3  *
   4  * Use, modification, and distribution are subject to the terms specified in the
   5  * COPYING file.
   6 **/
   7
   8 require("interactive.js");
   9 require("io.js");
  10 require("env.js");
  11
  12 function spawn_process_internal (program, args, blocking) {
  13     var process = Cc["@mozilla.org/process/util;1"]
  14         .createInstance(Ci.nsIProcess);
  15     process.init(find_file_in_path(program));
  16     return process.run(!!blocking, args, args.length);
  17 }
  18
  19 var PATH_programs = null;
  20 function get_shell_command_completer () {
  21     if (PATH_programs == null) {
  22         PATH_programs = [];
  23         var file = Cc["@mozilla.org/file/local;1"]
  24             .createInstance(Ci.nsILocalFile);
  25         for (var i = 0, plen = PATH.length; i < plen; ++i) {
  26             try {
  27                 file.initWithPath(PATH[i]);
  28                 var entries = file.directoryEntries;
  29                 while (entries.hasMoreElements()) {
  30                     var entry = entries.getNext().QueryInterface(Ci.nsIFile);
  31                     PATH_programs.push(entry.leafName);
  32                 }
  33             } catch (e) {}
  34         }
  35         PATH_programs.sort();
  36     }
  37     return prefix_completer($completions = PATH_programs,
  38                             $get_string = function (x) x);
  39 }
  40
  41 // use default
  42 minibuffer_auto_complete_preferences["shell-command"] = null;
  43
  44 /* FIXME: support a relative or full path as well as PATH commands */
  45 define_keywords("$cwd");
  46 minibuffer.prototype.read_shell_command = function () {
  47     keywords(arguments, $history = "shell-command");
  48     var prompt = arguments.$prompt || "Shell command [" + arguments.$cwd.path + "]:";
  49     var result = yield this.read(
  50         $prompt = prompt,
  51         $history = "shell-command",
  52         $auto_complete = "shell-command",
  53         $select,
  54         $validator = function (x, m) {
  55             var s = x.replace(/^\s+|\s+$/g, '');
  56             if (s.length == 0) {
  57                 m.message("A blank shell command is not allowed.");
  58                 return false;
  59             }
  60             return true;
  61         },
  62         forward_keywords(arguments),
  63         $completer = get_shell_command_completer());
  64     yield co_return(result);
  65 }
  66
  67 function find_spawn_helper () {
  68     var f = file_locator_service.get("CurProcD", Ci.nsIFile);
  69     f.append("conkeror-spawn-helper");
  70     if (f.exists())
  71         return f;
  72     return find_file_in_path("conkeror-spawn-helper");
  73 }
  74
  75 const STDIN_FILENO = 0;
  76 const STDOUT_FILENO = 1;
  77 const STDERR_FILENO = 2;
  78
  79 var spawn_process_helper_default_fd_wait_timeout = 1000;
  80 var spawn_process_helper_setup_timeout = 2000;
  81
  82 /**
  83  * @param program_name
  84  *        Specifies the full path to the program.
  85  * @param args
  86  *        An array of strings to pass as the arguments to the program.  The
  87  *        first argument should be the program name.  These strings must not
  88  *        have any NUL bytes in them.
  89  * @param working_dir
  90  *        If non-null, must be an nsILocalFile.  spawn_process will switch
  91  *        to this path before running the program.
  92  * @param finished_callback
  93  *        Called with a single argument, the exit code of the process, as
  94  *        returned by the wait system call.
  95  * @param failure_callback
  96  *        Called with a single argument, an exception, if one occurs.
  97  * @param fds
  98  *        If non-null, must be an object with only non-negative integer
  99  *        properties set.  Each such property specifies that the corresponding
 100  *        file descriptor in the spawned process should be redirected.  Note
 101  *        that 0 corresponds to STDIN, 1 corresponds to STDOUT, and 2
 102  *        corresponds to STDERR.  Note that every redirected file descriptor can
 103  *        be used for both input and output, although STDIN, STDOUT, and STDERR
 104  *        are typically used only unidirectionally.  Each property must be an
 105  *        object itself, with an input and/or output property specifying
 106  *        callback functions that are called with an nsIAsyncInputStream or
 107  *        nsIAsyncOutputStream when the stream for that file descriptor is
 108  *        available.
 109  * @param fd_wait_timeout
 110  *        Specifies the number of milliseconds to wait for the file descriptor
 111  *        redirection sockets to be closed after the control socket indicates
 112  *        the process has exited before they are closed forcefully.  A negative
 113  *        value means to wait indefinitely.  If fd_wait_timeout is null,
 114  *        spawn_process_helper_default_fd_wait_timeout is used instead.
 115  * @return
 116  *        A function that can be called to prematurely terminate the spawned
 117  *        process.
 118  */
 119 function spawn_process (program_name, args, working_dir,
 120                         success_callback, failure_callback, fds,
 121                         fd_wait_timeout) {
 122     var spawn_process_helper_program = find_spawn_helper();
 123     if (spawn_process_helper_program == null)
 124         throw new Error("Error spawning process: conkeror-spawn-helper not found");
 125     args = args.slice();
 126     if (args[0] == null)
 127         args[0] = (program_name instanceof Ci.nsIFile) ? program_name.path : program_name;
 128
 129     program_name = find_file_in_path(program_name).path;
 130
 131     const key_length = 100;
 132     const fd_spec_size = 15;
 133
 134     if (fds == null)
 135         fds = {};
 136
 137     if (fd_wait_timeout === undefined)
 138         fd_wait_timeout = spawn_process_helper_default_fd_wait_timeout;
 139
 140     var unregistered_transports = [];
 141     var registered_transports = [];
 142
 143     var server = null;
 144     var setup_timer = null;
 145
 146     const CONTROL_CONNECTED = 0;
 147     const CONTROL_SENDING_KEY = 1;
 148     const CONTROL_SENT_KEY = 2;
 149
 150     var control_state = CONTROL_CONNECTED;
 151     var terminate_pending = false;
 152
 153     var control_transport = null;
 154
 155     var control_binary_input_stream = null;
 156     var control_output_stream = null, control_input_stream = null;
 157     var exit_status = null;
 158
 159     var client_key = "";
 160     var server_key = "";
 161     // Make sure key does not have any 0 bytes in it.
 162     for (let i = 0; i < key_length; ++i)
 163         client_key += String.fromCharCode(Math.floor(Math.random() * 255) + 1);
 164
 165     // Make sure key does not have any 0 bytes in it.
 166     for (let i = 0; i < key_length; ++i)
 167         server_key += String.fromCharCode(Math.floor(Math.random() * 255) + 1);
 168
 169     var key_file_fd_data = "";
 170
 171     // This is the total number of redirected file descriptors.
 172     var total_client_fds = 0;
 173
 174     // This is the total number of redirected file descriptors that will use a socket connection.
 175     var total_fds = 0;
 176
 177     for (let i in fds) {
 178         if (fds.hasOwnProperty(i)) {
 179             if (fds[i] == null) {
 180                 delete fds[i];
 181                 continue;
 182             }
 183             key_file_fd_data += i + "\0";
 184             let fd = fds[i];
 185             if ('file' in fd) {
 186                 if (fd.perms == null)
 187                     fd.perms = 0666;
 188                 key_file_fd_data += fd.file + "\0" + fd.mode + "\0" + fd.perms + "\0";
 189                 delete fds[i]; // Remove it from fds, as we won't need to work with it anymore
 190             } else {
 191                 ++total_fds;
 192                 key_file_fd_data += "\0";
 193             }
 194             ++total_client_fds;
 195         }
 196     }
 197     var key_file_data = client_key + "\0" + server_key + "\0" + program_name + "\0" +
 198         (working_dir != null ? working_dir.path : "") + "\0" +
 199         args.length + "\0" +
 200         args.join("\0") + "\0" +
 201         total_client_fds + "\0" + key_file_fd_data;
 202
 203     function fail (e) {
 204         if (!terminate_pending) {
 205             terminate();
 206             if (failure_callback)
 207                 failure_callback(e);
 208         }
 209     }
 210
 211     function cleanup_server () {
 212         if (server) {
 213             server.close();
 214             server = null;
 215         }
 216         for (let i in unregistered_transports) {
 217             unregistered_transports[i].close(0);
 218             delete unregistered_transports[i];
 219         }
 220     }
 221
 222     function cleanup_fd_sockets () {
 223         for (let i in registered_transports) {
 224             registered_transports[i].transport.close(0);
 225             delete registered_transports[i];
 226         }
 227     }
 228
 229     function cleanup_control () {
 230         if (control_transport) {
 231             control_binary_input_stream.close();
 232             control_binary_input_stream = null;
 233             control_transport.close(0);
 234             control_transport = null;
 235             control_input_stream = null;
 236             control_output_stream = null;
 237         }
 238     }
 239
 240     function control_send_terminate () {
 241         control_input_stream = null;
 242         control_binary_input_stream.close();
 243         control_binary_input_stream = null;
 244         async_binary_write(control_output_stream, "\0", function () {
 245             control_output_stream = null;
 246             control_transport.close(0);
 247             control_transport = null;
 248         });
 249     }
 250
 251     function terminate () {
 252         if (terminate_pending)
 253             return exit_status;
 254         terminate_pending = true;
 255         if (setup_timer) {
 256             setup_timer.cancel();
 257             setup_timer = null;
 258         }
 259         cleanup_server();
 260         cleanup_fd_sockets();
 261         if (control_transport) {
 262             switch (control_state) {
 263             case CONTROL_SENT_KEY:
 264                 control_send_terminate();
 265                 break;
 266             case CONTROL_CONNECTED:
 267                 cleanup_control();
 268                 break;
 269                 /**
 270                  * case CONTROL_SENDING_KEY: in this case once the key
 271                  * is sent, the terminate_pending flag will be noticed
 272                  * and control_send_terminate will be called, so nothing
 273                  * more needs to be done here.
 274                  */
 275             }
 276         }
 277         return exit_status;
 278     }
 279
 280     function finished () {
 281         // Only call success_callback if terminate was not already called
 282         if (!terminate_pending) {
 283             terminate();
 284             if (success_callback)
 285                 success_callback(exit_status);
 286         }
 287     }
 288
 289     // Create server socket to listen for connections from the external helper program
 290     try {
 291         server = Cc['@mozilla.org/network/server-socket;1']
 292             .createInstance(Ci.nsIServerSocket);
 293
 294         var key_file = get_temporary_file("conkeror-spawn-helper-key.dat");
 295
 296         write_binary_file(key_file, key_file_data);
 297         server.init(-1 /* choose a port automatically */,
 298                     true /* bind to localhost only */,
 299                     -1 /* select backlog size automatically */);
 300
 301         setup_timer = call_after_timeout(function () {
 302             setup_timer = null;
 303             if (control_state != CONTROL_SENT_KEY)
 304                 fail("setup timeout");
 305         }, spawn_process_helper_setup_timeout);
 306
 307         function wait_for_fd_sockets () {
 308             var remaining_streams = total_fds * 2;
 309             var timer = null;
 310             function handler () {
 311                 if (remaining_streams != null) {
 312                     --remaining_streams;
 313                     if (remaining_streams == 0) {
 314                         if (timer)
 315                             timer.cancel();
 316                         finished();
 317                     }
 318                 }
 319             }
 320             for each (let f in registered_transports) {
 321                 input_stream_async_wait(f.input, handler, false /* wait for closure */);
 322                 output_stream_async_wait(f.output, handler, false /* wait for closure */);
 323             }
 324             if (fd_wait_timeout != null) {
 325                 timer = call_after_timeout(function() {
 326                     remaining_streams = null;
 327                     finished();
 328                 }, fd_wait_timeout);
 329             }
 330         }
 331
 332         var control_data = "";
 333
 334         function handle_control_input () {
 335             if (terminate_pending)
 336                 return;
 337             try {
 338                 let avail = control_input_stream.available();
 339                 if (avail > 0) {
 340                     control_data += control_binary_input_stream.readBytes(avail);
 341                     var off = control_data.indexOf("\0");
 342                     if (off >= 0) {
 343                         let message = control_data.substring(0,off);
 344                         exit_status = parseInt(message);
 345                         cleanup_control();
 346                         /* wait for all fd sockets to close? */
 347                         if (total_fds > 0)
 348                             wait_for_fd_sockets();
 349                         else
 350                             finished();
 351                         return;
 352                     }
 353                 }
 354                 input_stream_async_wait(control_input_stream, handle_control_input);
 355             } catch (e) {
 356                 // Control socket closed: terminate
 357                 cleanup_control();
 358                 fail(e);
 359             }
 360         }
 361
 362         var registered_fds = 0;
 363
 364         server.asyncListen(
 365             {
 366                 onSocketAccepted: function (server, transport) {
 367                     unregistered_transports.push(transport);
 368                     function remove_from_unregistered () {
 369                         var i;
 370                         i = unregistered_transports.indexOf(transport);
 371                         if (i >= 0) {
 372                             unregistered_transports.splice(i, 1);
 373                             return true;
 374                         }
 375                         return false;
 376                     }
 377                     function close () {
 378                         transport.close(0);
 379                         remove_from_unregistered();
 380                     }
 381                     var received_data = "";
 382                     var header_size = key_length + fd_spec_size;
 383
 384                     var in_stream, bin_stream, out_stream;
 385
 386                     function handle_input () {
 387                         if (terminate_pending)
 388                             return;
 389                         try {
 390                             let remaining = header_size - received_data.length;
 391                             let avail = in_stream.available();
 392                             if (avail > 0) {
 393                                 if (avail > remaining)
 394                                     avail = remaining;
 395                                 received_data += bin_stream.readBytes(avail);
 396                             }
 397                             if (received_data.length < header_size) {
 398                                 input_stream_async_wait(in_stream, handle_input);
 399                                 return;
 400                             } else {
 401                                 if (received_data.substring(0, key_length) != client_key)
 402                                     throw "Invalid key";
 403                             }
 404                         } catch (e) {
 405                             close();
 406                         }
 407                         try {
 408                             var fdspec = received_data.substring(key_length);
 409                             if (fdspec.charCodeAt(0) == 0) {
 410
 411                                 // This is the control connection
 412                                 if (control_transport)
 413                                     throw "Control transport already exists";
 414                                 control_transport = transport;
 415                                 control_output_stream = out_stream;
 416                                 control_input_stream = in_stream;
 417                                 control_binary_input_stream = bin_stream;
 418                                 remove_from_unregistered();
 419                             } else {
 420                                 var fd = parseInt(fdspec);
 421                                 if (!fds.hasOwnProperty(fd) || (fd in registered_transports))
 422                                     throw "Invalid fd";
 423                                 remove_from_unregistered();
 424                                 bin_stream = null;
 425                                 registered_transports[fd] = {transport: transport,
 426                                                              input: in_stream,
 427                                                              output: out_stream};
 428                                 ++registered_fds;
 429                             }
 430                             if (control_transport && registered_fds == total_fds) {
 431                                 cleanup_server();
 432                                 control_state = CONTROL_SENDING_KEY;
 433                                 async_binary_write(control_output_stream, server_key,
 434                                                    function (error) {
 435                                                        if (error != null)
 436                                                            fail(error);
 437                                                        control_state = CONTROL_SENT_KEY;
 438                                                        if (setup_timer) {
 439                                                            setup_timer.cancel();
 440                                                            setup_timer = null;
 441                                                        }
 442                                                        if (terminate_pending) {
 443                                                            control_send_terminate();
 444                                                        } else {
 445                                                            for (let i in fds) {
 446                                                                let f = fds[i];
 447                                                                let t = registered_transports[i];
 448                                                                if ('input' in f)
 449                                                                    f.input(t.input);
 450                                                                else
 451                                                                    t.input.close();
 452                                                                if ('output' in f)
 453                                                                    f.output(t.output);
 454                                                                else
 455                                                                    t.output.close();
 456                                                            }
 457                                                        }
 458                                                    });
 459                                 input_stream_async_wait(control_input_stream, handle_control_input);
 460                             }
 461                         } catch (e) {
 462                             fail(e);
 463                         }
 464                     }
 465
 466                     try {
 467                         in_stream = transport.openInputStream(Ci.nsITransport.OPEN_NON_BLOCKING, 0, 0);
 468                         out_stream = transport.openOutputStream(Ci.nsITransport.OPEN_NON_BLOCKING, 0, 0);
 469                         bin_stream = binary_input_stream(in_stream);
 470                         input_stream_async_wait(in_stream, handle_input);
 471                     } catch (e) {
 472                         close();
 473                     }
 474                 },
 475                 onStopListening: function (s, status) {
 476                 }
 477             });
 478
 479         spawn_process_internal(spawn_process_helper_program, [key_file.path, server.port], false);
 480         return terminate;
 481     } catch (e) {
 482         terminate();
 483
 484         if ((e instanceof Ci.nsIException) && e.result == Cr.NS_ERROR_INVALID_POINTER) {
 485             if (WINDOWS)
 486                 throw new Error("Error spawning process: not yet supported on MS Windows");
 487             else
 488                 throw new Error("Error spawning process: conkeror-spawn-helper not found");
 489         }
 490         // Allow the exception to propagate to the caller
 491         throw e;
 492     }
 493 }
 494
 495 /**
 496  * spawn_process_blind: spawn a process and forget about it
 497  */
 498 define_keywords("$cwd", "$fds");
 499 function spawn_process_blind (program_name, args) {
 500     keywords(arguments);
 501     /* Check if we can use spawn_process_internal */
 502     var cwd = arguments.$cwd;
 503     var fds = arguments.$fds;
 504     if (cwd == null && fds == null && args[0] == null)
 505         spawn_process_internal(program_name, args.slice(1));
 506     else {
 507         spawn_process(program_name, args, cwd,
 508                       null /* success callback */,
 509                       null /* failure callback */,
 510                       fds);
 511     }
 512 }
 513
 514
 515 //  Keyword arguments: $cwd, $fds
 516 function spawn_and_wait_for_process (program_name, args) {
 517     keywords(arguments, $cwd = null, $fds = null);
 518     var cc = yield CONTINUATION;
 519     spawn_process(program_name, args, arguments.$cwd,
 520                   cc, cc.throw,
 521                   arguments.$fds);
 522     var result = yield SUSPEND;
 523     yield co_return(result);
 524 }
 525
 526 // Keyword arguments: $cwd, $fds
 527 function shell_command_blind (cmd) {
 528     keywords(arguments);
 529     /* Check if we can use spawn_process_internal */
 530     var cwd = arguments.$cwd;
 531     var fds = arguments.$fds;
 532
 533     var program_name;
 534     var args;
 535
 536     if (POSIX) {
 537         var full_cmd;
 538         if (cwd)
 539             full_cmd = "cd \"" + shell_quote(cwd.path) + "\"; " + cmd;
 540         else
 541             full_cmd = cmd;
 542         program_name = getenv("SHELL") || "/bin/sh";
 543         args = [null, "-c", full_cmd];
 544     } else {
 545         var full_cmd;
 546         if (cwd) {
 547             full_cmd = "";
 548             if (cwd.path.match(/[a-z]:/i)) {
 549                 full_cmd += cwd.path.substring(0,2) + " && ";
 550             }
 551             full_cmd += "cd \"" + shell_quote(cwd.path) + "\" && " + cmd;
 552         } else
 553             full_cmd = cmd;
 554
 555         /* Need to convert the single command-line into a list of
 556             * arguments that will then get converted back into a *
 557             command-line by Mozilla. */
 558         var out = [null, "/C"];
 559         var cur_arg = "";
 560         var quoting = false;
 561         for (var i = 0; i < full_cmd.length; ++i) {
 562             var ch = full_cmd[i];
 563             if (ch == " ") {
 564                 if (quoting) {
 565                     cur_arg += ch;
 566                 } else {
 567                     out.push(cur_arg);
 568                     cur_arg = "";
 569                 }
 570                 continue;
 571             }
 572             if (ch == "\"") {
 573                 quoting = !quoting;
 574                 continue;
 575             }
 576             cur_arg += ch;
 577         }
 578         if (cur_arg.length > 0)
 579             out.push(cur_arg);
 580         program_name = "cmd.exe";
 581         args = out;
 582     }
 583     spawn_process_blind(program_name, args, $fds = arguments.$fds);
 584 }
 585
 586 function substitute_shell_command_argument (cmdline, argument) {
 587     if (!cmdline.match("{}"))
 588         return cmdline + " \"" + shell_quote(argument) + "\"";
 589     else
 590         return cmdline.replace("{}", "\"" + shell_quote(argument) + "\"");
 591 }
 592
 593 function shell_command_with_argument_blind (command, arg) {
 594     shell_command_blind(substitute_shell_command_argument(command, arg), forward_keywords(arguments));
 595 }
 596
 597 /**
 598  * Keyword arguments:
 599  * $cwd: The current working directory for the process.
 600  * $fds: File descriptors to use.
 601  */
 602 function shell_command (command) {
 603     if (!POSIX)
 604         throw new Error("shell_command: Your OS is not yet supported");
 605     var result = yield spawn_and_wait_for_process(getenv("SHELL") || "/bin/sh",
 606                                                   [null, "-c", command],
 607                                                   forward_keywords(arguments));
 608     yield co_return(result);
 609 }
 610
 611 function shell_command_with_argument (command, arg) {
 612     yield co_return((yield shell_command(substitute_shell_command_argument(command, arg), forward_keywords(arguments))));
 613 }
 614
 615 provide("spawn-process");